Ice removing means



Jan. 21, 1936. scoc 2,028,669

ICE REMOVING MEANS Filed Nov. 28, 1953 INVENTOR. 77101 7 Hiszzmk BYE; 2 i

; TTORNEY Eli) Patented Jan. 21, 1936 UNITED. STATES "PATEN T oFFIce assignments, to United Corporation, Chicago,

elaware Air Lines Transport. 111., a corporation of Application November 28,1933. Serial a... 700,052 4 Claims. (01. 244-31) This invention relates toice removing means and more particularly to means for removing an ice film from parts of airplanes exposed to ice forming conditions.

5 Under certain atmospheric conditions, ice may be formed upon objects, such as various parts of an airplane structure, moving through the air. This becomes of particular importance in airplanes, due not only to the added weight of the ice, but also to the change in effective shape of the airfoil surfaces, such as the wings, caused by an accumulation of ice on certain parts, such as the leading edge. This change of shape reduces the efficiency of the wing and causes a reduction in the lift coefllcient whichmay produce a condition in which the airplane can no longer maintain flight. It has been found that this ice becomes most troublesome, and forms the thickest layers in portions operating under a reduced pressure,

such as the upper surface at the leading edge of a wing.

It is an object of my invention to remove ice formation and/or prevent an accumulation of ice on such structures.

Other objects and advantages will be apparent fromthe accompanying specification and from the drawing which discloses what is now considered a preferred embodiment.

Fig. 1 is a somewhat diagrammatical sketch showing a cross-section of a structure having the invention applied thereto.

Fig. 2 is a perspective view of a structure, showing the covering applied thereon.

The invention, as shown is embodied in a memher Ill, such as an airplane wing, having a struc-- tural member I2 and a leading edge It. A flexible curtain or covering I6 is applied over the leading edge It of the member ill in such a manner that it can be drawn back and forth across that edge. If preferred, the covering l6 may be the envelope or skin, or a portion thereof, of the air-. foil, and may be moved across the airfoil edge, but, for convenience, in the embodiment disclosed the additional curtain or envelope is employed.

curtain or covering may be composed of any suitable flexible material such as a textile fabric or finely woven wire cloth. In order to reduce the friction between the curtain and the structure ID, a low freezing lubricant, such as.

talc powder, graphite or castor oil is supplied between the curtain and the surface it covers, or

' other friction reducing means, such as rollers, may be used. The outer or exposed surface of the curtain may be provided with a smooth and water repellent surface. In what is now con-' 'sidered the preferred embodiment, this surface is produced by applying a lacquer coating to the outer surface of the curtain. If the surface of the material is sufficiently smooth and water repelent, no treatment will, of course, be necessary.

It has been found in practice that ice is liable to form on the upper portion of the wing adjacent the leading edge. In applying my curtain to a wing, I have, therefore, found it desirable to cover that portion of the wing, but it should be understood that it'can be-applied to any portion, subject to the formation of ice. After a layer of ice has been formed which, of course, is formed on the curtain instead of on the surface it covers, the curtain is moved forward carrying the layer of ice therewith. The layer of ice when formed takes the shape of the structure which it is covering and which in most cases isa surface having a curvature of comparatively large radius. As the curtain is led forward across the leading edge of the structure which it covers, the curtain conforms to the shape of the structure and thus has a shape having a considerably smaller radius of curvature. Ice, not being sufflciently flexible, cannot take this new shape and it is, therefore, placed in such a position or condition that the relative wind will remove it.

Any suitable mechanism may be used for reciprocating this curtain or carrier. In the modification shown in the drawing, a reversible electric motor I8 is connected by means of a worm and wheel to a shaft 20 on which is secured a drum 22.

A cable 24 is wound around the drum 22 and secured thereon to prevent the the loops of the cable. The opposite ends ofthe cable 2!, which may take any suitable form such as a flat ribbon or an ordinary round cable, are secured in any suitable manner to the'opposite ends of the curtain. In the modification shown, this attachment is made by securing the cables in any suitable manner into sticks or reinforcing members 26 inserted in the ends of the curtain. The cables are guided in their reciprocating movements by any suitable means such as pulleys 26.

Any suitable means may be used to reverse the motor. In the embodiment shown, a gear 30 is secured to shaft 20 and drives a gear 32. The gear 32 has pins 34 and 36 thereon adapted to contact lever 38 of the toggle reversing switch 40. The curtain I6 is led across the leading edge I from the upper to the lower surface of the structure shown in Fig. 1 until pin 36 strikes the arm 38. Pin 36 then actuates toggle switch 40 to reversea portion of the current fed to the drum turning inside 35 motor I! and thereby reverse the motor, causing the curtain to be fed back across the leading edge of the structure from the bottom to the top thereof. A switch 42 is provided by means of which the operator can start or stop the movement of the curtain at will.

While I have shown one means of operating the curtain, it is to be expressly understood that I do not desire to limit myself to that particular means, it being obvious that various other means such as manually operated devices or fluid operated pistons and other means may be used to accomplish the same results.

It is also to be expressly understood that, al-

from, and sufliciently water repellent to prevent penetration of moisture therethrough in suiiicient quantity to cause freezing of the curtain to its supporting surface.

It is, therefore, to be understood that the invention is not limited to the specific embodiment herein described, but may be used in other ways and various changes may be: made therein without departing from the spirit and scope of the invention, as defined by the following claims.

What I claim is:

1. In an airplane: a wing having a leading edge whose radius of curvature is smaller than 2,028,609 that of adjacent portions of the wing, a strip of curtain snugly enveloping said leading edge and adjacent portions of the wing, and means for drawing said curtain back and forth about the leading edge of the wing while conforming the curtain thereto to break loose ice formations.

2. In an airplane: a wing having a leading edge whose radius of curvature is smaller than that of adjacent portions of the wing, a strip of ourtain snugly enveloping said leading edge and adjacent portions of the wing, and means for drawing said curtain back and forth about the leading edge of the wing while conforming the curtain thereto comprising a drum within said wing, flexible means connected to the ends of said curtain and having a driving connection with said drum, and a reversible motor having a driving connection with said drum.

3. In an airplane: a hollow wing structure tapering rearwardly from a leading edge; a fixed covering for said wing structure; a flexible envelope slidably mounted on the outside of said covering and enclosing the leading edge; and means for reciprocating said envelope about said leading edge while the airplane, is in flight to remove ice formed on said envelope.

4. A device as specified in claim 3, in which the means for reciprocating the envelope comprises cables connected to the upper and lower ends of the said envelope and extending through the wing covering into the wing structure, and means for alternately drawing inwardly the cables connected to the upper and lower ends of the envelope.

THORP I-IISCOCK. 

